Image processing method, and image processing apparatus

Abstract

The present invention provides an image processing method which includes recording an image by irradiating a recording medium with laser beams which are arrayed in parallel at predetermined intervals to heat the recording medium, so that the image is composed of a plurality of lines written with the laser beams on the recording medium, and wherein in the image recording, the plurality of lines written with the laser beams include a line written first and an overwritten line, a part of which is overlapped with the line written first; and the irradiation energy for the overwritten line is smaller than the irradiation energy for the line written first.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to an image processing method and an image processing apparatus for forming an image having an arbitrary line width with a plurality of image lines.[0003]2. Description of the Related Art[0004]Image recording and image erasing on a thermoreversible recording medium have been carried out so far by a contact method in which a heating source is brought into contact with a recording medium to heat the thermoreversible recording medium. As the heating source, in the case of image recording, a thermal head is generally used, and in the case of image erasing, a heat roller, a ceramic heater or the like is generally used.[0005]Such a contact image processing method has advantage in that, if a thermoreversible recording medium is a flexible material (e.g., a film, and paper sheet), an image can be uniformly recorded and erased by evenly pressing a heating source against a thermoreversible recording ...

AI Technical Summary

Benefits of technology

[0013]The present invention aims to solve the above-mentioned conventional problems and to achieve the following object. That is, the object of the present invention is to provide an image processing method and an image processing apparatus which are capable of precisely forming a predetermined line width of an image and securing high repetitive durability.

[0038]The present invention can solve the above-mentioned problems, achieve the object and provide an image processing method and image processing apparatus which enable precisely forming an image of lines having a predetermined line width and ensuring repetitive durability.

Problems solved by technology

However, when an RF-ID tag as disclosed in Japanese Patent Application Laid-Open (JP-A) No. 2004-265247 and Japanese Patent (JP-B) No. 3998193 is embedded in a thermoreversible recording medium, the thermoreversible recording medium needs to be thickened and the flexibility thereof degrades, and thus high pressure is required for uniformly pressing a heat source against the thermoreversible recording medium.

In addition, in the contact image processing method, a surface of the thermoreversible recording medium is scraped due to repetitive printing and erasure and irregularities are formed therein, and some parts are not in contact with a heating source (e.g., thermal head, and hot stamp).

Thus, the thermoreversible recording medium may not be uniformly heated, causing degradation in image density and erasing failure (see Japanese Patent (JP-B) No. 3161199 and Japanese Patent Application Laid-Open (JP-A) No. 09-30118).

However, in such a laser recording method, when an information-read code such as a two-dimensional code (e.g., character, bar code, and QR code) is recorded, but if an image having a predetermined line width is not precisely formed, the code may not be satisfactorily read through a machine, although the recorded image appears cleanly written visually.

Also, when lines are written on a recording medium in an overlapped manner in an attempt to write a line having a width greater than the beam diameter of a laser beam used, the thermoreversible recording medium is excessively heated due to accumulation of heat, causing degradation in the repetitive durability of the thermoreversible recording medium.

However, the above methods have drawbacks in that it is impossible to precisely form an image having a predetermined line width, and the repetitive durability of recording media degrades.

However, the above methods have a drawback in that the repetitive durability of recording media is poor, although it is possible to precisely form a predetermined line width.

Further, when an image is formed on a rewritable thermoreversible recording medium and if an excessive amount of energy is applied thereto, the thermoreversible recording medium is physically damaged, causing degradation in the repetitive durability.

However, when the irradiation energy is increased, unfavorably, the thermoreversible recording medium is physically damaged, causing degradation in repetitive durability, although the image is formed with a broader light width.

On the other hand, when the irradiation energy is reduced to prevent degradation of the repetitive durability of the thermoreversible recording medium, the image is formed with a narrower line width, however, the contrast (density) of the formed lines decreases, causing degradation in image quality.

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